When the graphics element is fairly complicated, either by virtue of the shape of its outline or else because of the shades of color to be obtained, the stage during which the pattern is printed, e.g. by silkscreen printing, by offset printing, or by some other method, can lead to failure, particularly if high standards are required for the quality of the pattern and of the colors. In the event of failure, cards whose patterns are judged to be of inadequate quality must be rejected. This means that the materials, components, and machining costs of the card manufacturing stages prior to the stage during which the pattern is made, are all lost. These costs are particularly high if the pattern is made after an electronic module has already been implanted in the card body. This situation arises particularly, but not exclusively, when the card is manufactured by molding the card body directly over the electronic module using the technique described in French patent application number 87/00446.
According to this technique, an electronic module is put into place in a mold whose cavity defines the outside shape to be given to the card body. After unmolding, a memory card is obtained having a card body in its final shape and in which an electronic module is already implanted. If the result of a subsequent pattern-imparting step is unacceptable, it will then be understood that the entire cost of making the card is lost.
Proposals have also been made to make the card body by injection molding a plastic material. This technique is described in European patent application number 267 826. In order to reduce manufacturing costs, the injected material is preferably acrylonitrile-butadiene-styrene (ABS). This material suffers from the drawback of being poorly suited to making patterns on the faces of the card body by conventional printing techniques of silkscreen printing or offset printing.
In order to remedy these drawbacks, an object of the invention is to provide a method of manufacturing a card, in particular a memory card, in which the stage during which a pattern is formed on the card body cannot of itself give rise to the card being rejected or which makes it possible to form a pattern independently of the nature of the material used for manufacturing the card body.